if there were a few people that were inclined to try this, i would love to do it sometime...
it is called painting with light.
examples of said photography (
the first image was produced using sparklers which is obvious because of the trails, but the second i'm not sure what was used...any theories?):
this techinque is achieved by using small aperture, long exposure time, preferably a dark/vacant of light place, black clothes, giant sparklers, and quick movement.